PLEASE NOTE: This article has been archived. It first appeared on ProRec.com in August 2000, contributed by then Staff Editor Barry Rudolph. We will not be making any updates to the article. Please visit the home page for our latest content. Thank you!
Microphones, for a recording engineer, have been likened to a painter’s brushes. The choice and use of certain mics for recording vocals and instruments have the greatest influence over the detail of the sonic pictures the recording engineer helps the producer and artist create.
Lead vocal recording is probably the most subjective and most variable area when it comes to microphone choice and placement. Vocal mics garner the most fame and notoriety because they can be part of the catalytic chemistry in the creation and realization of the ultimate vocal performance. Singers will demand a certain microphone to ensure themselves that they will have their own consistent and familiar vocal sound. Because of their intangible mystique – and their truly unique sound – vintage condenser microphones have gained tremendous respect. The demand for vintage condensers has also led to the creation of the refurbishing and restoration business for these increasingly rare treasures.
A number of vintage condensers are worth a mention. The venerable German-made Neumann condenser microphones remain the most widely popularized. The most popular Neumanns include the transistorized U87 and the earlier U67 and U47 tube microphones mostly used today. The esoteric M49 and M50 are quite good for lead vocals, and Neumann’s M149 tube model is a new, modern mic with the vintage heritage of the M49.
AKG from Austria is also very popular among artists and producers with the large diaphragm C12 leading the way. AKG has recently made a new version of this mic called the C12VR which is proving to be quite good for the modest sum of $4,000. Other good choices from AKG are: the C12A, C-414EB P48 or the C-414TLII. Also German-made is the Telefunken ELAM 251. This mic hasn’t been made for years, finding a restored one would set you back a little bit, but it would be well worth it. This mic offers a presence on vocals that cannot be duplicated any other way.
However, it is not to say only condensers should be used for vocal recording. In certain circumstances, there is nothing like the immediacy and impact that the right dynamic microphone can impart to a lead vocalist’s sound. The Sennheiser MD421, Shure SM7, and EV RE20 microphones have been used on many recordings to great effect.
Vocal Mic Placement
Mic placement – particularly when using sensitive condensers – directly affects every aspect of the singer’s sound and performance. As engineer, I am obsessed with and stressed over how the singer addresses the mic in every way.
While there are no hard and fast rules, ideally the singer needs to sing directly, i.e. on-axis into the diaphragm of the mic. Distance to the mic is extremely important because our ears relate distance to intimacy with the singer’s voice and emotion: closer distances equate to a more intimate sound.
Off-axis singing or changing distance causes a degradation in quality but is all part of “working the mic,” which is part of a singer’s on-mic sound. Experienced singers use these physics to enhance or color the good and bad areas of their voice. A good singer will use slight distance changes for dramatic punctuation.
Working very close to the mic nearly always necessitates the use of a “pop filter” of some type to attenuate air blasts from the mouth. All cardioid microphones exhibit the “proximity” effect which boosts low frequencies as the singer gets closer to the diaphragm. Singers can use this effect to achieve a larger, fatter tone.
In general, a good starting point mic placement is slightly higher than the singer’s mouth. The mic is then aimed downward at the mouth with the exact distance at the singer’s and producer’s option. I have seen thousands of ways singers approach singing into a mic and only cite the above example as just one way. I have recorded singers who insisted on lying down on the studio floor, naked with a hand-held mic, the studio monitors blasting away, in total wanton abandonment.
The miking and recording of percussion is also highly subjective in both placement and choice. Drum kits and percussion, being loud instruments, excite the acoustics of a given space and so the decision to utilize this “room sound” or divorce it from the recording is crucial in mic choice and placement.
In general, the closer the microphone to the drum the less the room ambience will add to the final drum sound. If the kit sounds good and balanced in the room, you may want to mix in the sound from distant room mics. In pop recordings, engineers and producers usually prefer a very close, present drum sound (at least as a starting point). They will close-mic every drum in a drum kit, or in the case of a percussion instrument like conga drums, a separate mic for each drum.
Favorite mics for this “close miking” technique are split between dynamics and condensers. For tom-toms and snare drums I like Shure’s Beta 57 or Sennheiser’s MD421U. These dynamics can really take the high SPL sound level that comes a few inches from a well-hit drum. I like to use condensers sometimes for close-miking as they achieve a “taller” sound with more highs and more lows. Condensers will work better if your drummer/percussionist has a lighter touch and more “finesse”. My choices for condensers would be U-87’s, C-414EB’s or AKG C-451’s or C-452’s.
For overhead mics that retrieve the overall kit sound including the cymbals and some of the room tone, I like C-414-TLII’s, C12A’s or sometimes C-452’s. Good condenser choices for snare drums are: C-452, Neumann KM84, Sony C-37A (tube). This is one method of recording percussion instruments. There are literally thousands of mic choices and placement ideas. I think back at some of the better drum sounds I got, and recall an whole album I did where I used nothing better than $50 dynamic microphones on all the drums. The producer got more calls on the great sound on the drums than anything else.
Electric guitars are easy to mic and record. Guitar amps can be miked with dynamic mics like the Shure Beta 57 or Electro-Voice RE-20 or even a Beyer ribbon mic. The first decision is whether you would like a cabinet sound or just a single speaker sound. Engineers mic just one speaker by placing the mic directly on a single speaker in the cabinet (hopefully not the shredded one but the thrashed one). Moving the mic anywhere from touching the grill cloth to a foot away will do the job. The proximity effect works here, so by keeping the mic close to the speaker you are enhancing the low frequencies. High frequencies are directional, so if you align directly on the center of the speaker cone, you will get the most high frequencies available. As you move the mic further away, you lose lows and as you move the mic laterally towards the outer edge of the speaker cone, you lose highs.
If you are going to go for a cabinet sound, then everything changes. The mic is now about a foot or more from the cabinet and centered on the collection of speakers in the cab. If you are using an open back amp, try putting a mic behind the amp as well as the front. Phase cancellation can work for you or against you here. You can also place a mic out in the room and mix that sound to the guitar sound.
I am making all of this mic placement process sound very subjective because it is. Experiment a lot if you have the wherewithal. Especially when miking the speaker, minute changes in mic placement can make tremendous changes in the sound.
The sound of the acoustic guitar emanates from the sound hole, the vibrating top plate and the exact point at which you are picking or strumming. I usually use a single mic starting right over the sound hole where you will get the most low frequency energy. I put the mic above the low E string and point it downward. From then on, I move the mic all over the place looking for the “sweet spot” that works best for the way the musician plays, the natural sound of that particular guitar and the way the guitar part needs to sound in the production.
Move the mic towards the bridge and you will get less lows with more attack and brilliance. Move towards the neck, you end up with less attack, a little less low-end, maybe more fret noise and a more mellow sound. It is impossible to say exactly what I would do in any particular situation. The guitar’s sound is dependent on the player’s technique, the instrument itself, the key of the song and the condition of the strings.
I like to use either a B&K 4001, AKG C-452 or Audio-Technica AT-4041 condenser mics. One of the best sounds I got on an acoustic guitar was with a Sony “tie-tack” lapel mic I taped to a stick from an ice cream bar and then placed inside of the guitar. This worked, as the player refused to sit or stand in front of a stationary microphone.
Any bass player will tell you that usually in the studio their instrument is “taken direct”. I always thought bass players has it easy when it came to cartage: they just bring their ax and we engineers had to deal with it.
The “direct” sound of the bass guitar is used more often than not. I usually start with the instrument’s volume and tone knobs wide open. Some bass players will use instruments with active electronics. These active basses can sound great live, and be a real pain in the studio because their sound is so hyperactive.
I find that a very good transformer (to change the high impedance of the instrument’s output to the low input impedance of the console) is the secret to a good sounding direct bass. What the engineer does with it in terms of processing is another matter.
I generally always use a compressor after the equalizer. The less electronics in the signal path of the bass going to tape, the better. I like the Teletronix LA-2A, Summit tube or a DBX-165 (without peak stop) compressors. Miking a bass amp for a more live and realistic bass guitar sound requires a good bass rig and mics like the EV RE-20, AKG D-12 or the newer D-112 dynamic mic. Unless you want room sound, stick the mic right on the speaker.
For more great information on recording bass, read Bruce Richardson’s article, “A Kick in the Bass.”
Bass players are my favorite people, so I work hard to get them a fat sound.